Recombinant DNA technology and click chemistry: a powerful combination for generating a hybrid elastin-like-statherin hydrogel to control calcium phosphate mineralization

• Mohamed Hamed Misbah,
• Mercedes Santos,
• Luis Quintanilla,
• Christina Günter,
• Matilde Alonso,
• Andreas Taubert and
• José Carlos Rodríguez-Cabello

Beilstein J. Nanotechnol. 2017, 8, 772–783, doi:10.3762/bjnano.8.80

• biology experiments for gene construction were performed using standard methods. ELR production was carried out using cellular systems for genetically engineered protein biosynthesis in E. coli and purification was performed with several cycles of temperature-dependent reversible precipitation. After

Vapor deposition routes to conformal polymer thin films

• Priya Moni,
• Ahmed Al-Obeidi and
• Karen K. Gleason

Beilstein J. Nanotechnol. 2017, 8, 723–735, doi:10.3762/bjnano.8.76

• that controlled protein adsorption [16]. Martin et al. used iCVD deposited conformal coatings of poly(dimethylaminomethylstyrene) on nylon fabric as antimicrobial agents again E. Coli and B. subtilis, as shown in Figure 6f [27]. Xu et al. demonstrated the benefit of iCVD over plasma enhanced polymer

Uptake of the proteins HTRA1 and HTRA2 by cells mediated by calcium phosphate nanoparticles

• Olga Rotan,
• Katharina N. Severin,
• Simon Pöpsel,
• Alexander Peetsch,
• Melisa Merdanovic,
• Michael Ehrmann and
• Matthias Epple

Beilstein J. Nanotechnol. 2017, 8, 381–393, doi:10.3762/bjnano.8.40

• proteins HTRA1 and HTRA2 HTRA1 was produced and purified as described previously [45]. BL21 DE3-Rosetta E. coli cells were used to express HTRA2 with an N-terminal His-tag (pET28a Vector containing codons 134-458 of HTRA2, a kind gift from Antonis S. Zervos, University of Central Florida). HTRA2 expression

Reconstitution of the membrane protein OmpF into biomimetic block copolymer–phospholipid hybrid membranes

• Matthias Bieligmeyer,
• Franjo Artukovic,
• Stephan Nussberger,
• Thomas Hirth,
• Thomas Schiestel and
• Michaela Müller

Beilstein J. Nanotechnol. 2016, 7, 881–892, doi:10.3762/bjnano.7.80

• . The protein was purified from E. coli membranes by differential extractions using SDS at temperatures of 50 and 37 °C, followed by dialysis against 1% octyl-POE. The monomeric and trimeric forms of OmpF were observed in boiled and unboiled samples, respectively. Channel activity of OmpF in planar

Novel roles for well-known players: from tobacco mosaic virus pests to enzymatically active assemblies

• Claudia Koch,
• Fabian J. Eber,
• Carlos Azucena,
• Alexander Förste,
• Stefan Walheim,
• Thomas Schimmel,
• Alexander M. Bittner,
• Holger Jeske,
• Hartmut Gliemann,
• Sabine Eiben,
• Fania C. Geiger and
• Christina Wege

Beilstein J. Nanotechnol. 2016, 7, 613–629, doi:10.3762/bjnano.7.54

• occasionally [87][94][134][162]. Heterologously expressed TMV CP species offer more degrees of freedom for modifications. However, CP from E. coli does not organize into TLPs with RNA efficiently since it lacks an N-terminal post-translational acetylation; and up to now the yield of TLPs from eukaryotic yeast

• % surface coverage [88]. This work has recently been extended to a related potyvirus, potato virus A (PVA), which could be fashioned with similar surface density not only with 4CL2, but also with a two-enzyme mix of 4CL2 and stilbene synthase (STS) expressed in E. coli, or with a fusion protein of both

Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution

• Brunella Perito,
• Emilia Giorgetti,
• Paolo Marsili and
• Maurizio Muniz-Miranda

Beilstein J. Nanotechnol. 2016, 7, 465–473, doi:10.3762/bjnano.7.40

• antibacterial tests and their MIC and minimum bactericidal concentration (MBC) values were obtained against E. coli and B. subtilis. To have a known antimicrobial as a reference, we also tested ampicillin against the two bacteria. The results are shown in Table 2. In order to detect the time of appearance of

• the AgNPs bactericidal effects, E. coli cultures with and without AgNPs at the MBC value were prepared in microtiter plates and their optical density and viable count were determined at time zero and after 45 min, 2 h, 3 h and 24 h of incubation at 37 °C. The results of the viable count E. coli

• cultures are reported in Table 3 for ns-ablated AgNPs. E. coli cultures tested with AgNPsH2Ons (18.4 μg/mL) and AgNPsLiClns (3.7 μg/mL) did not show any increase of optical density at any monitored time, while E. coli cultures without additives showed an optical density increase starting from 2 h, until

Sonochemical co-deposition of antibacterial nanoparticles and dyes on textiles

• Ilana Perelshtein,
• Anat Lipovsky,
• Nina Perkas,
• Tzanko Tzanov and
• Aharon Gedanken

Beilstein J. Nanotechnol. 2016, 7, 1–8, doi:10.3762/bjnano.7.1

• after leaching experiments was characterized by reflectance measurements. Antibacterial test The antibacterial activity was tested according to the procedure described by our group previously [25]. Briefly, the antibacterial activity of MO- and MO/dye-coated fabrics was tested against E. coli. Overnight

• with the dye are presented. The antibacterial properties of the ZnO and CuO were first evaluated against E. coli, and compared with co-deposited dye/MO. Two and a half log reduction was obtained in 1 h for the ZnO coated bandage. The addition of RO16 or RB5 slightly reduced the antibacterial activity

Ultrastructural changes in methicillin-resistant Staphylococcus aureus induced by positively charged silver nanoparticles

• Dulce G. Romero-Urbina,
• Humberto H. Lara,
• J. Jesús Velázquez-Salazar,
• M. Josefina Arellano-Jiménez,
• Eduardo Larios,
• Anand Srinivasan,
• Jose L. Lopez-Ribot and
• Miguel José Yacamán

Beilstein J. Nanotechnol. 2015, 6, 2396–2405, doi:10.3762/bjnano.6.246

• permeability [38]. After penetrating the cell membrane, AgNPs can also alter sulfur-containing amino acids and phosphorus (a main constituent of DNA), inhibiting replication via attaching to the bacterial ribosome [39][40]. The proteomic signatures of AgNP-treated E. coli demonstrated an accumulation of

Functionalization of α-synuclein fibrils

• Simona Povilonienė,
• Vida Časaitė,
• Virginijus Bukauskas,
• Arūnas Šetkus,
• Juozas Staniulis and
• Rolandas Meškys

Beilstein J. Nanotechnol. 2015, 6, 124–133, doi:10.3762/bjnano.6.12

• was constructed as described in the Experimental section. After expression in E. coli BL21 (DE3) cells, α-SynC141 was found as a soluble protein and the level of expression was the same as that of a native α-Syn. The presence of the additional amino acid in the C-terminus did not affect the solubility

• ′-TACTCGAGTTAACAGGCTTCAGGTTCGTAG-3′ (Metagene). The obtained PCR fragment was digested with XbaI and XhoI restriction endonucleases (Thermo Scientific) and inserted into the corresponding sites of the pET21a(+) vector (Novagen). The ligation mixture was transferred into E. coli DH5α. Positive clones were identified by PCR

• . [46], with some modifications. For the preparation of recombinant proteins, pET21α-SynC141 and pRK172 plasmids containing α-synC141 and α-syn genes respectively were introduced into E. coli BL21 (DE3) cells by electroporation. 5 mL of the overnight culture were used to inoculate 1 L of NB media

Interaction of dermatologically relevant nanoparticles with skin cells and skin

• Annika Vogt,
• Fiorenza Rancan,
• Sebastian Ahlberg,
• Berouz Nazemi,
• Chun Sik Choe,
• Maxim E. Darvin,
• Sabrina Hadam,
• Ulrike Blume-Peytavi,
• Kateryna Loza,
• Jörg Diendorf,
• Matthias Epple,
• Christina Graf,
• Eckart Rühl,
• Martina C. Meinke and
• Jürgen Lademann

Beilstein J. Nanotechnol. 2014, 5, 2363–2373, doi:10.3762/bjnano.5.245

• stress and cell damage. The results are in accordance with reports in the literature, e.g., differential tolerance to AgNP depending on chloride concentrations and ionic strength and Ag+-induced oxidative stress in E. coli was recently demonstrated by Chambers et al. [41]. Biological responses to

Carbon nano-onions (multi-layer fullerenes): chemistry and applications

• Juergen Bartelmess and
• Silvia Giordani

Beilstein J. Nanotechnol. 2014, 5, 1980–1998, doi:10.3762/bjnano.5.207

• biological marking of D. melanogaster, they used fluorescent CNOs also as imaging agents to study E. coli and C. elegans in vivo [51]. In a recent report from our group [40], we used fluorescein-functionalized CNOs in a comparative toxicological study in vitro and in vivo, including biological marking

Antimicrobial properties of CuO nanorods and multi-armed nanoparticles against B. anthracis vegetative cells and endospores

• Pratibha Pandey,
• Merwyn S. Packiyaraj,
• Himangini Nigam,
• Gauri S. Agarwal,
• Beer Singh and
• Manoj K. Patra

Beilstein J. Nanotechnol. 2014, 5, 789–800, doi:10.3762/bjnano.5.91

• , generated on copper foil as effective antibacterial against E. coli bacteria when the bacterial suspension drop was tested on these surfaces. Perelshtein et al. [19] have reported antibacterial CuO-cotton textile against E. coli and S. aureus. Gao et al. [20] reported strong antibacterial activity of CuO

• against gram-positive B. anthracis vegetative cells almost comparable to that against nonsporigenic gram-negative E. coli bacteria. The CuO nanoparticles demonstrated a significantly higher bactericidal activity in comparison to bulk CuO microparticles. The spores however showed more resistance towards

• and spores B. anthracis and E. coli bacteria were grown in nutrient broth in an incubator shaker at 37 °C overnight and were used for evaluation of nanoparticles in broth culture test. Standard cultures of the bacteria B. anthracis Sterne and E. coli were sourced from the High Containment Facility of

An ultrasonic technology for production of antibacterial nanomaterials and their coating on textiles

• Anna V. Abramova,
• Vladimir O. Abramov,
• Aharon Gedanken,
• Ilana Perelshtein and
• Vadim M. Bayazitov

Beilstein J. Nanotechnol. 2014, 5, 532–536, doi:10.3762/bjnano.5.62

• the surface of textile at very high velocities. Fabrics coated with ZnO nanoparticles by using the developed method showed good antibacterial activity against E. coli. Keywords: antibacterial textile; cavitation; electrical discharge in liquid; nanoparticle; ultrasound; Introduction Currently, the

• second set the suspension produced by the sonoplasma discharge was immediately used to impregnate the textile. The same concentration of ZnO NPs was used in both experiments. The antibacterial activity of the two sample sets against E. coli was tested by using the standard method BS EN ISO 20743:2007 [12

• activity against E. coli of the two sets of fabrics. Figure 7 shows the results of these tests. It is clearly visible that the antibacterial activity of the textile coated by the sonoplasma particles against E. coli is higher than the fabric coated with industrial NP’s. This might be explained as the

Photocatalytic antibacterial performance of TiO₂ and Ag-doped TiO₂ against S. aureus. P. aeruginosa and E. coli

• Kiran Gupta,
• R. P. Singh,
• Ashutosh Pandey and
• Anjana Pandey

Beilstein J. Nanotechnol. 2013, 4, 345–351, doi:10.3762/bjnano.4.40

• investigated against Gram-positive Staphylococcus aureus (S. aureus), and Gram-negative Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli) bacteria under visible light. Results and Discussion XRD of TiO2 and Ag-doped TiO2 The samples were annealed at 450 °C to achieve crystallization in TiO2

• both concentrations (3% and 7%) were toxic to all the bacteria tested. However, application of 7% doped Ag–TiO2 nanoparticles killed 100% P. aeruginosa cells at 40 mg/30 mL concentration, while 5% and 4% viabilities of S. aureus and E. coli were obtained, respectively. It is also clear from Figure 6

• nanoparticles at 60 mg/30 mL of culture, 0% viability in the case of P. aeruginosa was recorded, while in the case of S. aureus and E. coli 7% and 3% viabilities were recorded. Therefore 7% doped silver nanoparticles at 60 mg/30 mL of bacterial culture (0.2 O.D. at 660 nm) is the optimum concentration for the

Electrospinning preparation and electrical and biological properties of ferrocene/poly(vinylpyrrolidone) composite nanofibers

• Ji-Hong Chai and
• Qing-Sheng Wu

Beilstein J. Nanotechnol. 2013, 4, 189–197, doi:10.3762/bjnano.4.19

• PVP nanofibers. X-ray diffraction (XRD) results showed that the crystalline structure of Fc in the fibers was amorphous after the electrospinning process. A biological evaluation of the antimicrobial activity of Fc/PVP nanofibers was carried out by using Gram-negative Escherichia coli (E. coli) as

• centre of the agar plate killed the bacteria over and around them (Figure 6b), which showed that the composite Fc/PVP nanofibers obviously inhibited growth of the E. coil. It can be explained that Fc is lipophilic in nature and able to pass through the cell membrane. When E. coli is in contact with Fc

• demonstrated that the morphologies and diameters of nanofibers could be controlled by adjusting the type of solvents and Fc concentration. These electrospun Fc/PVP nanofibers had bactericidal activity against the Gram-negative bacteria E. coli, and the glassy carbon electrode modified with Fc/PVP nanofibers

Growth behaviour and mechanical properties of PLL/HA multilayer films studied by AFM

• Cagri Üzüm,
• Johannes Hellwig,
• Narayanan Madaboosi,
• Dmitry Volodkin and
• Regine von Klitzing

Beilstein J. Nanotechnol. 2012, 3, 778–788, doi:10.3762/bjnano.3.87

• , back in 1993 [9]. Further measurements include different strains of E. coli with a colloidal probe [10], elastic modulus of human platelet cells [11], human bone cell or skeletal muscle cells [12], breast cancer cells [13][14], hydrogel films [15][16][17], or nanoribbons [18], as well as single

Paper modified with ZnO nanorods – antimicrobial studies

• Mayuree Jaisai,
• Sunandan Baruah and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2012, 3, 684–691, doi:10.3762/bjnano.3.78

• ) nanoparticles embedded into a paper matrix have been reported as exhibiting antibacterial properties [4]. Wallpaper prepared by using zinc oxide nanoparticle (~20 nm) coatings has been reported to render antibacterial surfaces that inhibit growth of bacteria such as Escherichia coli (E. coli) [5]. An increase

• in cellular internalization of ZnO nanoparticles has also been observed by Appierot et al. [6] in a study of their antibacterial effect on E. coli and S. aureus. This work reports on an antimicrobial paper containing zinc oxide (ZnO) nanorods grown by a hydrothermal process, and which can be used for

• of organic dyes using similar paper embedded with ZnO nanorods [21]. In this work we report the antimicrobial activities of paper functionalized by in situ growth of ZnO nanorods through a hydrothermal process. Results and Discussion Studies on the photocatalytic immobilization of E. coli and S

FTIR nanobiosensors for Escherichia coli detection

• Stefania Mura,
• Gianfranco Greppi,
• Maria Laura Marongiu,
• Pier Paolo Roggero,
• Sandeep P. Ravindranath,
• Lisa J. Mauer,
• Nicoletta Schibeci,
• Francesco Perria,
• Massimo Piccinini,
• Plinio Innocenzi and
• Joseph Irudayaraj

Beilstein J. Nanotechnol. 2012, 3, 485–492, doi:10.3762/bjnano.3.55

• due to enterohaemorrhagic E. coli (Escherichia coli) have a low incidence but can have severe and sometimes fatal health consequences, and thus represent some of the most serious diseases due to the contamination of water and food. New, fast and simple devices that monitor these pathogens are

• necessary to improve the safety of our food supply chain. In this work we report on mesoporous titania thin-film substrates as sensors to detect E. coli O157:H7. Titania films treated with APTES ((3-aminopropyl)triethoxysilane) and GA (glutaraldehyde) were functionalized with specific antibodies and the

• absorption properties monitored. The film-based biosensors showed a detection limit for E. coli of 1 × 102 CFU/mL, constituting a simple and selective method for the effective screening of water samples. Keywords: biosensors; E. coli; FTIR spectroscopy; foodborne pathogens; nanomaterials; Introduction

Mapping mechanical properties of organic thin films by force-modulation microscopy in aqueous media

• Jianming Zhang,
• Zehra Parlak,
• Carleen M. Bowers,
• Terrence Oas and
• Stefan Zauscher

Beilstein J. Nanotechnol. 2012, 3, 464–474, doi:10.3762/bjnano.3.53

• thermal evaporator (Kurt Lesker PVD 75), and subsequently cleaned by ozone plasma ashing (Emitech K-1050X). Protein monolayer Five tandem B-domains of staphylococcal protein A were expressed and purified from E. coli. The C-terminus of the terminal protein was modified with cysteine to enable protein